Here’s my updated company history on G. Genschow, collated from a number of sources including “Der Munitions-Verband”. Not all references agree on some of this info (eg when the Durlach factory was acquired) but this compilation is as accurate as I have been able to establish using the better references where possible.
The arms and ammunition business of GUSTAV GENSCHOW operated from 1887 till 1959.
Gustav Genschow (b1862-1940, see image) was a former clerk of Lindener/Egestorff. Being ambitious, he left Egestorff at the age of 25 and founded his own ammunition wholesale business in Berlin on 25 Aug 1887.
In 1890, his brother in-law William Seebach joined the business and the business name was named GUSTAV GENSCHOW & Co, Berlin. In the same year a retail store was purchased allowing both retail and wholesale trade. Their first catalog was also produced in 1890. This company eventually became one of the biggest German enterprises in the field of trade of weapons, ammunition, hunting and rifle accessories including exports.
In 1899 Genschow purchased the “Badischen Schrot und Gewehrpfropfenfabrik GmbH” (Baden Shot and Rifle Factory) in Baden which was established in 1888. In doing this they also moved into the manufacture of ammunition and eventually they also manufactured guns and leather goods until WW II.
In Feb 1903 G.Genschow purchased the larger “Badische Sprengkapsel, Zündhütchen und Munitionsfabrick E.SCHREINER” at Durlach from BASSE and SELVE. This factory was formed in 1897 by Ernst Schreiner. Initially only primers were produced there. Gustav Genschow & Co now becomes GUSTAV GENSCHOW & Co, AG - a type of corporation. They expand the plant and now have the capability of manufacturing considerable ammunition.
In May 1903 Genschow changes the name of the “Badische Sprengkapsel, Zündhütchen und Munitionsfabrick E.SCHREINER” to “Durlacher Zündhütchen und Patronenfabrick GmbH, Durlach I/Bd”. In 1904 the “Badischen Schrot und Gewehrpfropfenfabrik GmbH” and “Durlacher Zündhütchen und Patronenfabrick GmbH” are amalgamated to form the “Badischen Munitionsfabrik GmbH” at Durlach. That company used a " B.M. D" hs.
In 1906 the “Badischen Munitionsfabrik GmbH” is merged fully into GUSTAV GENSCHOW & Co and a Cologne branch is also established. In 1908 a Hamburg branch is established.
Exactly how much ammunition Genschow produced at this stage is unknown but about then Genschow started to produce ammunition using the early “GG&Co” and “G G C” hs. A 1908 Genschow catalog shows no “Geco” tradename or “Geco” ammunition, just Egestorff, Utendoerffer (RWS), DWM and Savage.
In 1907 GUSTAV GENSCHOW & Co becomes a joint-stock company and is known as GUSTAV GENSCHOW & Co AG. The company then progressively expands:
-1908 an export department is opened in Hamburg.
-1912 a subsidary GUSTAV GENSCHOW & Co GmbH was formed in Vienna. This became an independent company known as Gustav Genschow “NOBEL” GmbH, Vienna and existed until 2005 when it became part of Ruag.
-1920 a Buenos Aires agency is established in Argentina (becomes 'Geco Compania Industria Comercial S.A." in 1924),
-1921 Konigsberg branch and sales departments at Franckurt-am-Main and Nuremburg,
-1922 Leather/canvas goods factory in Westerwald,
-1923 agencies in Rio de Janeiro, Brazil (becomes 'Sociedade Geco Limitida" in 1925) and Valparaiso, Chile (becomes Compania Geco Limitada" in 1930).
-1924 : The company acquired the Inventory of DWA.
From the Erfurt Conference of 1909, Genschow was allocated the “D” letter for their hs representing production at their “Durlach” factory.
The trademark “GECO” was registered by G. Genschow in 1922 but had been used since 1919 (eg M1919 Geco Sporting Rifle).
In 1927 I.G. Farbenindustrie puchased Genschow and RWS. A working agreement with RWS was formed and from that time, (handgun) ammunition production from both companies was practically identical and may have been produced in the same factory - prob GECO. Some 1930 Geco packets exist contained cartridges with RWS hs.
Offices at Berlin were kept until at least 1933 and in 1934 they moved to Hamburg. Gustuv Genschow died in 1940.
After WW2 in 1959 all shares were taken over by Dynamit Nobel A.G (DN) and in 1962 the company was renamed DYNAMIT-NOBEL-GENSCHOW GmbH. Dynamit Nobel continued to produce pistol ammunition with a ‘GECO’ hs.
In 1963 ownershop of the company is tranferred to Dynamit Nobel AG. The plant is finally closed in 1972 and dismantled in the following years.
From April 2002, the Swiss ammunition manufacturer RUAG Munition and Dynamit Nobel AmmoTec in Germany merged their ammunition businesses and formed the RUAG Ammotec company. They took over Dynamit Nobel RWS ammunition and the “GECO” tradename was still used after time on ammunition.
Some time shortly after 2002, the use of the “Geco” hs sporting rifle ammunition in the commoner calibres began to reappear - note the lowercase letters. These cases are believed to have been produced by Norma which had also been taken over by Ruag Ammotech AG in 2002.
From January 2005 Gustav Genschow “Nobel” (the Austrian branch) is renamed RUAG Ammotec Austria, now also part of the Ruag conglomeration.